1. Field of Invention
The present invention relates to an image transmission system that transmits image data through telecommunication means; in particular, it relates to an image transmission system wherein image data captured with an electronic image device such as an electronic camera is transmitted via an image relay apparatus such as a gateway server to an image storage device such as an image server on the Internet and stored there, and image data stored in an image storage device such as an image server on the Internet is downloaded to and browsed in an electronic image device such as an electronic camera via an image relay apparatus such as a gateway server; the invention furthermore relates to the image relay apparatus and electronic image device used in the image transmission system.
2. Description of Related Art
There has been active development of image transmission systems wherein all the image data captured with an electronic camera is transmitted via telecommunication lines to an externally located high capacity storage device (image server) and stored there, and the image data stored in the image server is used (browsed, printed, distributed, etc.) by making use of the various image services offered by the image server.
For example, image data transmission systems are known, wherein image data captured with an electronic camera is transmitted to and stored on a personal computer or image server on the Internet or the like using a digital data transmission function built into the electronic camera or a digital data transmission function of a portable telephone connected to the digital camera; image data stored on a personal computer or image server on the Internet or the like is received by the electronic camera using the digital data transmission function built into the electronic camera or the digital data transmission function of a portable telephone connected to the electronic camera; and received image data is displayed on the liquid crystal display of the electronic camera and viewed.
Such image transmission systems have the following advantages.                Large capacity built-in memory or removable memory for storing image data becomes unnecessary, so the cost of the electronic camera can be reduced.        All the image data is stored on a specific image server, so the benefits of post-processing services (printing, etc.) can be expected.        The user of the electronic camera only has to depress the shutter button to have the image data stored on an image server, so in cases such as where image print orders are placed over the Internet, the effort of having to transmit image data to the image server that performs the printing service from one's electronic camera or memory card can be done away with.        
In such an image data transmission system, there are limits to the storage capacity of the storage area (album) allocated to a single user of the image server, and if the data size of the image data that one wishes to newly store exceeds the available capacity of the aforementioned album, it would be necessary to delete some of the image data stored in the album to increase the available capacity of the aforementioned album, or to register with a different image server and open a new album. Or else, whenever storing image data, one would have to designate an album with available capacity from among several albums to store the image data in that album. Such operations are very bothersome and a source of anguish for users with little knowledge of image transmission systems, especially children and the elderly, and such a situation arising while taking pictures would end the enjoyment of taking pictures, and as a result has been a cause that has impeded the general adoption of such image transmission systems. Moreover, even for users with extensive knowledge of image transmission systems, such operations are time consuming, and there have been situation where photo opportunities have been lost as a result.
In this connection, an object of the present invention is to provide an image transmission system that allows image data transmission operations to be carried out in a reliable, efficient and simple manner, as well as providing an image relay apparatus and electronic image device used in the image transmission system.